Add "antctl proxy" support

With this command antctl can operate as a reverse proxy for Antrea APIs,
similarly to "kubectl proxy" for the K8s APIs (we rely on the
k8s.io/kubectl Go module for the implementation). Thanks to this,
troubleshooting the APIs can become much easier and we hide complexity
from clients. One example is that it becomes much easier to use "go tool
pprof". The drawback here is that the HTTPS connection between the proxy
and the Antrea Agent / Controller is not secure (this can be fixed for
the Controller at least); in this it is very similar to the
supportbundle command implementation.

Fixes #1434

TODO: documentation

go.mod

@@ -58,6 +58,7 @@ require (
 	k8s.io/klog v1.0.0
 	k8s.io/kube-aggregator v0.18.4
 	k8s.io/kube-openapi v0.0.0-20200410145947-61e04a5be9a6
+	k8s.io/kubectl v0.18.4
 	k8s.io/utils v0.0.0-20200410111917-5770800c2500
 )
 

go.sum

@@ -12,6 +12,7 @@ github.com/Azure/go-autorest/tracing v0.5.0/go.mod h1:r/s2XiOKccPW3HrqB+W0TQzfbt
 github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
+github.com/MakeNowJust/heredoc v0.0.0-20170808103936-bb23615498cd/go.mod h1:64YHyfSL2R96J44Nlwm39UHepQbyR5q10x7iYa1ks2E=
 github.com/Mellanox/sriovnet v1.0.1 h1:g9FqYgcybIuDHKDy8ZEaILeTSXo0r0jzqTFK8rpUSas=
 github.com/Mellanox/sriovnet v1.0.1/go.mod h1:zikbXOU755fnTeF858ym1z4BkQsWYOgW4RpoYCXre/g=
 github.com/Microsoft/go-winio v0.4.11/go.mod h1:VhR8bwka0BXejwEJY73c50VrPtXAaKcyvVC4A4RozmA=
@@ -57,6 +58,7 @@ github.com/cenkalti/rpc2 v0.0.0-20140912135055-44d0d95e4f52/go.mod h1:v2npkhrXyk
 github.com/cenkalti/rpc2 v0.0.0-20180727162946-9642ea02d0aa h1:t+iWhuJE2aropY4uxKMVbyP+IJ29o422f7YAd73aTjg=
 github.com/cenkalti/rpc2 v0.0.0-20180727162946-9642ea02d0aa/go.mod h1:v2npkhrXyk5BCnkNIiPdRI23Uq6uWPUQGL2hnRcRr/M=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
+github.com/chai2010/gettext-go v0.0.0-20160711120539-c6fed771bfd5/go.mod h1:/iP1qXHoty45bqomnu2LM+VVyAEdWN+vtSHGlQgyxbw=
 github.com/cheggaaa/pb/v3 v3.0.4 h1:QZEPYOj2ix6d5oEg63fbHmpolrnNiwjUsk+h74Yt4bM=
 github.com/cheggaaa/pb/v3 v3.0.4/go.mod h1:7rgWxLrAUcFMkvJuv09+DYi7mMUYi8nO9iOWcvGJPfw=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
@@ -107,8 +109,10 @@ github.com/d2g/hardwareaddr v0.0.0-20190221164911-e7d9fbe030e4/go.mod h1:bMl4RjI
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/daviddengcn/go-colortext v0.0.0-20160507010035-511bcaf42ccd/go.mod h1:dv4zxwHi5C/8AeI+4gX4dCWOIvNi7I6JCSX0HvlKPgE=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumCAMpl/TFQ4/5kLM=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
+github.com/docker/distribution v2.7.1+incompatible/go.mod h1:J2gT2udsDAN96Uj4KfcMRqY0/ypR+oyYUYmja8H+y+w=
 github.com/docker/docker v0.7.3-0.20190327010347-be7ac8be2ae0/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/go-units v0.4.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
 github.com/docker/spdystream v0.0.0-20160310174837-449fdfce4d96 h1:cenwrSVm+Z7QLSV/BsnenAOcDXdX4cMv4wP0B/5QbPg=
@@ -129,6 +133,8 @@ github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7
 github.com/evanphx/json-patch v4.2.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
 github.com/evanphx/json-patch v4.5.0+incompatible h1:ouOWdg56aJriqS0huScTkVXPC5IcNrDCXZ6OoTAWu7M=
 github.com/evanphx/json-patch v4.5.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
+github.com/exponent-io/jsonpath v0.0.0-20151013193312-d6023ce2651d/go.mod h1:ZZMPRZwes7CROmyNKgQzC3XPs6L/G2EJLHddWejkmf4=
+github.com/fatih/camelcase v1.0.0/go.mod h1:yN2Sb0lFhZJUdVvtELVWefmrXpuZESvPmqwoZc+/fpc=
 github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
@@ -173,6 +179,9 @@ github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5y
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.2 h1:6nsPYzhq5kReh6QImI3k5qWzO4PEbvbIW2cwSfR/6xs=
 github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golangplus/bytes v0.0.0-20160111154220-45c989fe5450/go.mod h1:Bk6SMAONeMXrxql8uvOKuAZSu8aM5RUGv+1C6IJaEho=
+github.com/golangplus/fmt v0.0.0-20150411045040-2a5d6d7d2995/go.mod h1:lJgMEyOkYFkPcDKwRXegd+iM6E7matEszMG5HhwytU8=
+github.com/golangplus/testing v0.0.0-20180327235837-af21d9c3145e/go.mod h1:0AA//k/eakGydO4jKRoRL2j92ZKSzTgj9tclaCrvXHk=
 github.com/google/btree v0.0.0-20180813153112-4030bb1f1f0c/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
 github.com/google/btree v1.0.0 h1:0udJVsspx3VBr5FwtLhQQtuAsVc79tTq0ocGIPAU6qo=
 github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
@@ -248,6 +257,8 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/pty v1.1.5/go.mod h1:9r2w37qlBe7rQ6e1fg1S/9xpWHSnaqNdHD3WcMdbPDA=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/liggitt/tabwriter v0.0.0-20181228230101-89fcab3d43de/go.mod h1:zAbeS9B/r2mtpb6U+EI2rYA5OAXxsYw6wTamcNW+zcE=
+github.com/lithammer/dedent v1.1.0/go.mod h1:jrXYCQtgg0nJiN+StA2KgR7w6CiQNv9Fd/Z9BP0jIOc=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/mailru/easyjson v0.0.0-20160728113105-d5b7844b561a/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
 github.com/mailru/easyjson v0.0.0-20190614124828-94de47d64c63/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
@@ -272,6 +283,7 @@ github.com/mdlayher/netlink v1.0.0/go.mod h1:KxeJAFOFLG6AjpyDkQ/iIhxygIUKD+vcwqc
 github.com/mdlayher/netlink v1.1.0 h1:mpdLgm+brq10nI9zM1BpX1kpDbh3NLl3RSnVq6ZSkfg=
 github.com/mdlayher/netlink v1.1.0/go.mod h1:H4WCitaheIsdF9yOYu8CFmCgQthAPIWZmcKp9uZHgmY=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
+github.com/mitchellh/go-wordwrap v1.0.0/go.mod h1:ZXFpozHsX6DPmq2I0TCekCxypsnAUbP2oI0UX1GXzOo=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
@@ -283,6 +295,7 @@ github.com/munnerz/goautoneg v0.0.0-20120707110453-a547fc61f48d/go.mod h1:+n7T8m
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
+github.com/mxk/go-flowrate v0.0.0-20140419014527-cca7078d478f h1:y5//uYreIhSUg3J1GEMiLbxo1LJaP8RfCpH6pymGZus=
 github.com/mxk/go-flowrate v0.0.0-20140419014527-cca7078d478f/go.mod h1:ZdcZmHo+o7JKHSa8/e818NopupXU1YMK5fe1lsApnBw=
 github.com/olekukonko/tablewriter v0.0.0-20170122224234-a0225b3f23b5/go.mod h1:vsDQFd/mU46D+Z4whnwzcISnGGzXWMclvtLoiIKAKIo=
 github.com/onsi/ginkgo v0.0.0-20151202141238-7f8ab55aaf3b/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
@@ -295,6 +308,7 @@ github.com/onsi/gomega v0.0.0-20170829124025-dcabb60a477c/go.mod h1:C1qb7wdrVGGV
 github.com/onsi/gomega v1.7.0 h1:XPnZz8VVBHjVsy1vzJmRwIcSwiUO+JFfrv/xGiigmME=
 github.com/onsi/gomega v1.7.0/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
 github.com/opencontainers/go-digest v0.0.0-20180430190053-c9281466c8b2/go.mod h1:cMLVZDEM3+U2I4VmLI6N8jQYUd2OVphdqWwCJHrFt2s=
+github.com/opencontainers/go-digest v1.0.0-rc1/go.mod h1:cMLVZDEM3+U2I4VmLI6N8jQYUd2OVphdqWwCJHrFt2s=
 github.com/opencontainers/runc v0.0.0-20190115041553-12f6a991201f/go.mod h1:qT5XzbpPznkRYVz/mWwUaVBUv2rmF59PVA73FjuZG0U=
 github.com/opencontainers/runtime-spec v0.1.2-0.20190507144316-5b71a03e2700/go.mod h1:jwyrGlmzljRJv/Fgzds9SsS/C5hL+LL3ko9hs6T5lQ0=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
@@ -386,6 +400,7 @@ github.com/wenyingd/ofnet v0.0.0-20201015012029-21df99f8161d h1:wjTew5yHsgqNXpQP
 github.com/wenyingd/ofnet v0.0.0-20201015012029-21df99f8161d/go.mod h1:oF9872TvzJqLzLKDGVMItRLWJHlnwXluuIuNbOP5WKM=
 github.com/xiang90/probing v0.0.0-20190116061207-43a291ad63a2 h1:eY9dn8+vbi4tKz5Qo6v2eYzo7kUS51QINcR5jNpbZS8=
 github.com/xiang90/probing v0.0.0-20190116061207-43a291ad63a2/go.mod h1:UETIi67q53MR2AWcXfiuqkDkRtnGDLqkBTpCHuJHxtU=
+github.com/xlab/handysort v0.0.0-20150421192137-fb3537ed64a1/go.mod h1:QcJo0QPSfTONNIgpN5RA8prR7fF8nkF6cTWTcNerRO8=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
 go.etcd.io/bbolt v1.3.3 h1:MUGmc65QhB3pIlaQ5bB4LwqSj6GIonVJXpZiaKNyaKk=
 go.etcd.io/bbolt v1.3.3/go.mod h1:IbVyRI1SCnLcuJnV2u8VeU0CEYM7e686BmAb1XKL+uU=
@@ -564,6 +579,7 @@ k8s.io/apimachinery v0.18.4 h1:ST2beySjhqwJoIFk6p7Hp5v5O0hYY6Gngq/gUYXTPIA=
 k8s.io/apimachinery v0.18.4/go.mod h1:OaXp26zu/5J7p0f92ASynJa1pZo06YlV9fG7BoWbCko=
 k8s.io/apiserver v0.18.4 h1:pn1jSQkfboPSirZopkVpEdLW4FcQLnYMaIY8LFxxj30=
 k8s.io/apiserver v0.18.4/go.mod h1:q+zoFct5ABNnYkGIaGQ3bcbUNdmPyOCoEBcg51LChY8=
+k8s.io/cli-runtime v0.18.4/go.mod h1:9/hS/Cuf7NVzWR5F/5tyS6xsnclxoPLVtwhnkJG1Y4g=
 k8s.io/code-generator v0.18.4/go.mod h1:TgNEVx9hCyPGpdtCWA34olQYLkh3ok9ar7XfSsr8b6c=
 k8s.io/component-base v0.18.4 h1:Kr53Fp1iCGNsl9Uv4VcRvLy7YyIqi9oaJOQ7SXtKI98=
 k8s.io/component-base v0.18.4/go.mod h1:7jr/Ef5PGmKwQhyAz/pjByxJbC58mhKAhiaDu0vXfPk=
@@ -577,16 +593,21 @@ k8s.io/kube-aggregator v0.18.4 h1:OoQD9bbA+blyhcppPMCEabngLaJ/PJNc4ksNr8tyIzY=
 k8s.io/kube-aggregator v0.18.4/go.mod h1:xOVy4wqhpivXCt07Diwdms2gonG+SONVx+1e7O+GfC0=
 k8s.io/kube-openapi v0.0.0-20200410145947-61e04a5be9a6 h1:Oh3Mzx5pJ+yIumsAD0MOECPVeXsVot0UkiaCGVyfGQY=
 k8s.io/kube-openapi v0.0.0-20200410145947-61e04a5be9a6/go.mod h1:GRQhZsXIAJ1xR0C9bd8UpWHZ5plfAS9fzPjJuQ6JL3E=
+k8s.io/kubectl v0.18.4 h1:l9DUYPTEMs1+qNtoqPpTyaJOosvj7l7tQqphCO1K52s=
+k8s.io/kubectl v0.18.4/go.mod h1:EzB+nfeUWk6fm6giXQ8P4Fayw3dsN+M7Wjy23mTRtB0=
+k8s.io/metrics v0.18.4/go.mod h1:luze4fyI9JG4eLDZy0kFdYEebqNfi0QrG4xNEbPkHOs=
 k8s.io/utils v0.0.0-20200324210504-a9aa75ae1b89/go.mod h1:sZAwmy6armz5eXlNoLmJcl4F1QuKu7sr+mFQ0byX7Ew=
 k8s.io/utils v0.0.0-20200410111917-5770800c2500 h1:iwoQwtHT3aQtbNKwKlQ2HdCTxv3thi/Tog6lLqIpdO8=
 k8s.io/utils v0.0.0-20200410111917-5770800c2500/go.mod h1:sZAwmy6armz5eXlNoLmJcl4F1QuKu7sr+mFQ0byX7Ew=
 rsc.io/quote/v3 v3.1.0/go.mod h1:yEA65RcK8LyAZtP9Kv3t0HmxON59tX3rD+tICJqUlj0=
 rsc.io/sampler v1.3.0/go.mod h1:T1hPZKmBbMNahiBKFy5HrXp6adAjACjK9JXDnKaTXpA=
 sigs.k8s.io/apiserver-network-proxy/konnectivity-client v0.0.7 h1:uuHDyjllyzRyCIvvn0OBjiRB0SgBZGqHNYAmjR7fO50=
 sigs.k8s.io/apiserver-network-proxy/konnectivity-client v0.0.7/go.mod h1:PHgbrJT7lCHcxMU+mDHEm+nx46H4zuuHZkDP6icnhu0=
+sigs.k8s.io/kustomize v2.0.3+incompatible/go.mod h1:MkjgH3RdOWrievjo6c9T245dYlB5QeXV4WCbnt/PEpU=
 sigs.k8s.io/structured-merge-diff/v3 v3.0.0-20200116222232-67a7b8c61874/go.mod h1:PlARxl6Hbt/+BC80dRLi1qAmnMqwqDg62YvvVkZjemw=
 sigs.k8s.io/structured-merge-diff/v3 v3.0.0 h1:dOmIZBMfhcHS09XZkMyUgkq5trg3/jRyJYFZUiaOp8E=
 sigs.k8s.io/structured-merge-diff/v3 v3.0.0/go.mod h1:PlARxl6Hbt/+BC80dRLi1qAmnMqwqDg62YvvVkZjemw=
 sigs.k8s.io/yaml v1.1.0/go.mod h1:UJmg0vDUVViEyp3mgSv9WPwZCDxu4rQW1olrI1uml+o=
 sigs.k8s.io/yaml v1.2.0 h1:kr/MCeFWJWTwyaHoR9c8EjH9OumOmoF9YGiZd7lFm/Q=
 sigs.k8s.io/yaml v1.2.0/go.mod h1:yfXDCHCao9+ENCvLSE62v9VSji2MKu5jeNfTrofGhJc=
+vbom.ml/util v0.0.0-20160121211510-db5cfe13f5cc/go.mod h1:so/NYdZXCz+E3ZpW0uAoCj6uzU2+8OWDFv/HxUSs7kI=

pkg/antctl/antctl.go

@@ -23,6 +23,7 @@ import (
 	"github.com/vmware-tanzu/antrea/pkg/agent/apiserver/handlers/ovstracing"
 	"github.com/vmware-tanzu/antrea/pkg/agent/apiserver/handlers/podinterface"
 	"github.com/vmware-tanzu/antrea/pkg/agent/openflow"
+	"github.com/vmware-tanzu/antrea/pkg/antctl/raw/proxy"
 	"github.com/vmware-tanzu/antrea/pkg/antctl/raw/supportbundle"
 	"github.com/vmware-tanzu/antrea/pkg/antctl/raw/traceflow"
 	"github.com/vmware-tanzu/antrea/pkg/antctl/transform/addressgroup"
@@ -406,6 +407,11 @@ var CommandList = &commandList{
 			supportAgent:      true,
 			supportController: true,
 		},
+		{
+			cobraCommand:      proxy.Command,
+			supportAgent:      false,
+			supportController: true,
+		},
 	},
 	codec: scheme.Codecs,
 }